A technique for determining the internal osmotic concentration of a small nematode using a modified nanolitre osmometer is described and used to investigate osmoregulation in the Antarctic nematode Panagrolaimus davidi. This technique enables the osmotic concentration to the measured with an accuracy of +/-12 mmol kg(-1). The pattern of melting in the nematode's different body compartments sugg...

The ontogeny of osmoregulation was studied in laboratory-reared early developmental stages of the Chinese mitten crab Eriocheir sinensis from the Elbe estuary (North Sea, Germany). At salinities ranging from 0.16 to 44.3‰, survival rate was quantified, hemolymph osmolality was measured, and osmoregulatory capacity was calculated as the difference between osmolality of the hemolymph and that of ...

The peptidase system in Drosophila melanogaster, consisting of dipeptidase-A, dipeptidase-B, dipeptidase-C and the leucine aminopeptidases, was used as a model to study the adaptive significance of enzyme activity variation. The involvement of the peptidases in osmoregulation has been suggested from the ubiquitous distribution of peptidase activities in nearly all tissues and the high concentra...

Barnacles are sessile macro-invertebrates, found along rocky shores in coastal areas worldwide. The euryhaline bay barnacle Balanus improvisus (Darwin, 1854) (= Amphibalanus improvisus) can tolerate a wide range of salinities, but the molecular mechanisms underlying the osmoregulatory capacity of this truly brackish species are not well understood. Aquaporins are pore-forming integral membrane ...

The spiny dogfish shark (Squalus acanthias) is one of the most commonly used cartilaginous fishes in biological research, especially in the fields of nitrogen metabolism, ion transporters and osmoregulation. Nonetheless, transcriptomic data for this organism is scarce. In the present study, a multi-tissue RNA-seq experiment and de novo transcriptome assembly was performed in four different spin...

Intestinal fluids of most marine teleosts are alkaline (pH 8.4-9.0) and contain high levels of HCO(3)(-) equivalents (40-130 mM) which are excreted at a significant rate (>100 microEq kg(-1) h(-1)). Recent research reveals the following about this substantial HCO(3)(-) secretion: (1) It is not involved in acid-base regulation or neutralisation of stomach acid, but increases in parallel with dri...

Osmoregulation is a vital physiological function for fish, as it helps maintain a stable intracellular concentration of ions in environments of variable salinities. We focused on a primarily freshwater species, the European whitefish (Coregonus lavaretus), to investigate the molecular mechanisms underlying salinity tolerance and examine whether these mechanisms differ between genetically simila...

The phenotypic variation in osmotic adjustment (OA) capacity of five Bulgarian winter durum wheat genotypes and their progenies was determined using a modified method based on the measurement of seedling growth suppression after three-day exposure to osmotic stress induced by 1 mol/L sucrose. The genetic parameters of the studied trait in a diallel crossing scheme, including the selected genoty...